回答

<?php
$videosrc = "0.53 RkP:/ 复制打开抖音，看看【信马游疆的作品】听闻远方有你，动身跋涉千里，看伊犁最美的草原# 旅行... https://v.douyin.com/6asKovn/";

preg_match("/(https:[\w\W]+)+/", $videosrc, $match);
if (count($match) != 2) {
    echo "地址不对";
    return;
}
$_realurl = $match[0];

$headers = get_headers($_realurl, 1);
if (isset($headers['Location'])) {
    if (is_array($headers['Location'])) {
        $_realurl = end($headers['Location']);
    } else {
        $_realurl = $headers['Location'];
    }
}

preg_match("/video\/([\d]+)+/", $_realurl, $matchs);
if (count($matchs) != 2) {
    echo "视频地址不对";
    return;
}


$data = file_get_contents("https://www.iesdouyin.com/web/api/v2/aweme/iteminfo/?item_ids={$matchs[1]}");
$getdata = json_decode($data, true);
$_url = $getdata['item_list'][0]['video']['play_addr']['url_list'][0];

$downloadurl = str_replace('wm', '', $_url); //得到vid
//echo $downloadurl;


$filename = "test.mp4"; //路径文件名
echo $downloadurl;
return;
$headersss = get_headers($downloadurl, 1);
var_dump($headersss);
if (isset($headersss['Location'])) {
    if (is_array($headersss['Location'])) {
        $_realurls = end($headersss['Location']);
    } else {
        $_realurls = $headersss['Location'];
    }
}
echo $_realurls;//这个是真实的无水印视频下载地址